[PATCH 2.39] Always define __USE_TIME_BITS64 when 64 bit time_t is used

[Florian Weimer]

* Florian Weimer via Libc-stable:

> From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
>
> It was raised on libc-help [1] that some Linux kernel interfaces expect
> the libc to define __USE_TIME_BITS64 to indicate the time_t size for the
> kABI.  Different than defined by the initial y2038 design document [2],
> the __USE_TIME_BITS64 is only defined for ABIs that support more than
> one time_t size (by defining the _TIME_BITS for each module).
>
> The 64 bit time_t redirects are now enabled using a different internal
> define (__USE_TIME64_REDIRECTS). There is no expected change in semantic
> or code generation.
>
> Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu, and
> arm-linux-gnueabi
>
> [1] https://sourceware.org/pipermail/libc-help/2024-January/006557.html
> [2] https://sourceware.org/glibc/wiki/Y2038ProofnessDesign
>
> Reviewed-by: DJ Delorie <dj@redhat.com>
> (cherry picked from commit a4ed0471d71739928a0d0fa3258b3ff3b158e9b9)

Adhemerval, any thoughts about the backport to 2.39?

Thanks,
Florian